The present invention relates to a new and improved construction of a hay harvesting machine.
Generally speaking, the hay harvesting machine of the present development is of the type comprising at least one rake wheel revolving about a substantially vertical or upright shaft and contains a driven rotatable housing part or portion rotatably mounted upon the upright shaft. At the rotatable housing portion there are mounted a plurality of tine supports equipped with rake tines or prongs. The tine supports can be selectively brought into each of two operating positions by rotation thereof about an axis extending transversely with respect to their lengthwise axis and approximately parallel to the upright shaft. The tine supports are connected by means of a hinge connection with a control element which continuously engages with a control track or cam which is non-rotatably mounted at the upright shaft. In the first operating position of the tine supports there can be established a control connection by blocking the hinge connection between the control element and the tine supports. This control connection brings about pivoting or rocking of the tine supports about their lengthwise axis during their revolving motion. In the second operating position no control connection exists, in that there is released the hinge connection between the control element and the tine supports, and the tine supports are now secured against rocking or pivoting about their lengthwise axis.
A similar type of hay harvesting machine is known from German Patent Publication No. 2,619,867 and the corresponding U.S. Pat. No. 4,059,944, wherein the control elements, hingedly coupled with the tine supports, are guided in a control cam or track. This control track extends at the same spacing about the upright shaft and possesses, in the direction of the upright shaft, an ascending and again descending portion or section for raising the rake tines during swath formation. Due to the space required by the control track or cam in the direction of the upright shaft, it is therefore necessary to correspondingly increase the structural height of the machine, and thus also its weight. This increased weight of the equipment requires a corresponding design and dimensioning thereof. Due to the relatively large structural height the use of the machine at the region of hedges, bushes and trees having low slung branches is rendered more difficult, if not made impossible.